To study the power and transmission system's power division of compound helicopter in its particular flight style

a comprehensive performance calculation model that consists of the mathematical model combining the aerodynamics parts and mechanical drive system parts was established. By limiting the flight conditions

the compound helicopter's transition flight border was established. After calculating the power of different routes in the transition flight border

what impact the aerodynamics parts and mechanical drive system parts had on the compound helicopter during the transition flight was analyzed. By a ground test simulating power division in that flight style

the date validation for mathematical model was made. Although there is error of 6% between the computing result and the experimental result

the accuracy has been improved 4% compared with the traditional calculation method. According to this method

it's possible to establish a more effective compound helicopter performance calculation method.